Clutch problems

[ae86 slide]

i have a ADM sprinter with 20v silvertop, adm T50, and a clutch which is really starting to give me the sh#ts.

heres the story so far.
about a month ago at QR, my clutch went really firm and stated slipping i assumed it was the clutch line being to close to the extractors and boiling the fluid, so i wrapped the line in heat wrap and replaced the fluid. problem solved, not quite.

next hard drive, after a few clutch kicks it did it again. firm clutch pedal, clutch slipping, so i drove sraight home and the pedal slowly got softer. this time decided it had something to do with the throw out bearing as it had been squelling for a while.

so i pulled the box out and to my suprise there was a nice spray of oil inside the bell housing. Rear main seal had gone. so replaced rear main seal, clutch disk (not pressure plate as it was only 6 months old) and throw out bearing. sweet, problem solved,

Then a few days later, back to the testing ground (late night industrial estate). after 4 or 5 clutch kicks did it again. only this time wen i pulled over i couldnt get it back into any gear, turned off the car for ten minutes, then it was ok, pedal was still firm for most of the drive home. so decided it must be hydrolics so i replaced master and slave clutch cylinders.
did this on sunday, went for drive last night took the first few corners with hand brake then tried a right hander with clutch kick, straight away started free reving all the way down the road, so pulled over banged it out of 2nd and sure enough firm pedal and couldnt get it into gear.
sat for 10 minutes checking it every 2 minutes trying to get it into gear, then after the 3rd try pedal was nomal again went straight into gear and drove off normally.

WHAT IS THE PROBLEM?
sorry bout the huge post but i want everyone to get all the info so someone can help me. im now thinking its the pressure plate, but at this point ive decided to stop guessing. can someone with some knowlege tell me wats wrong with it.

thanks, jason

[Hyuga]

sorry I'm not answering your problem, but what do people normally do on the clutch line with an ADM gearbox? as my clutch slave is just sit right next to my extractor with only tiny bit of clearance.

[mattysshop]

organic clutch discs don't like heat..swap over to a metallic or carbide pad type clutch disc, they work better when they get warm (to a degree)..did you spray thinners over the contact areas a few times to clean any oil resedue?

Matty

p.s. just don't do what i did.. 4 puck metalic button type disc, with a 2000lbs built up TRD p/plate..they kill T-50's http://www.ae86drivingclub.com.au/forums/emoticons/smile.gif

[Monster]

See what really impresses me is that you tried to solve the problem yourself first before posting, rather than just putting up "My clutch isn't working and feels weird... whats wrong with it?"

Ok, a couple of stupid questions...
* When you converted it to 20v, you did put in the pilot bearing?
* When you put in the new clutch, you did wear the clutch in before doing 'clutch kicks'?
* What size clutch are you using? The 200mm or the 212mm
* How are your synchros?

As for the clutch line being so close to the extractors, most people convert there slave to MA60 which has its inlet on the end, then run a long steel braided line up and against the fire wall. This not only gives you better pedal feel, but also will not melt!

[3sglevin]

Gday, I would suggest it was a presure plate problem or that & clutch plate, for the pedal to be firm it tells me the hydraulic system is fine. If the fluid was boiling, it then gets bubbles of air in it as it boils, so the pedal would go soft not hard.
do you have a heavy duty clutch plate/preasure plate? If not then I would have these checked.

You said you replaced the clutch plate, not the presure plate. Are they a match? perhaps there is a problem there.

just my thoughts

[ae86 slide]

* When you converted it to 20v, you did put in the pilot bearing?[/b]
i did not do the conversion it was done about a year ago

* When you put in the new clutch, you did wear the clutch in before doing 'clutch kicks'?[/b]
for prob 2 or 3 days

* What size clutch are you using? The 200mm or the 212mm[/b]
212mm

* How are your synchros?[/b]
not sure but the gear box used to grind when i would do a burnout in first and try to grab second and keep wheel spinning. havnt tried that for a while though. and also i thought if it was a gear box problem it wouldnt free rev it would grind or something?

as for 3sglevins questions

do you have a heavy duty clutch plate/preasure plate[/b]
no just standard

You said you replaced the clutch plate, not the presure plate. Are they a match? perhaps there is a problem there.[/b]
pretty sure, compared clutch disks old and new before installing and they looked the same, same diamiter,
thanks for the help so far guys

[Monster]

Ok, if the pilot/spigot bearing is missing or rooted then it could spell a whole heap of trouble, there cheap enough to swap when you change your rear main and or clutch. as far as you synchros, yeah it sounds like there rooted, 2nd gear is usually the first to go. It will still free rev but will be hard to put in or out of gears, also might pop out under load.

One last question, did you adjust your clutch peddle when you changed the clutch?

[mattysshop]

if you didn't put your spigot bearing in you would know by know..you would have gone through a T-50 real quick!

[3sglevin]

I dont know how good a standard clutch is? but I am pretty sure you really need a better one, for what you want to do with it. Levinracer has a TRD clutch and flywheel in the for sale section, I would guess it would take that kind of punishment alot better.

[ae86 slide]

thanks for the help fellas, a brake and clutch place said it could be movement in my crank! wich is moving the fly wheel around, and yeah i do agree that the TRD one would be a wise move and also if syncros are stuffed wouldnt it make bad noises and grind not free rev?
thanks again fellas

[ae86 slide]

O.K. i think i have the answer
i was talking to a clutch specialist this morning who came to the conclusion that my clutch line that runs past my extractors was old and absorbing alot of heat, his theory was that the flexible line, (being made up of multiple layers of material) had developed a split on the inside wich after high revs and high heat flares open, creating a pocket in between the layers of material wich catches the fluid and therefore does not operate the slave properly.
does this seem possible?
it seemed to make sense to me.
Im replacing the line tomorrow so i will post my results
i thought this was important to post as most 86's have there line and slave running close to extractors.
jason

[ae86 slide]

so far so good, instantly improved pedal feel, alot lighter, and so far no slipping or firmness.

[mattysshop]

nice having a JDM 86, so you don;t run into these dramas.. http://www.ae86drivingclub.com.au/forums/emoticons/smile.gif just joking fellas

[SPEEDCORE]

Originally posted by ae86 slide@Sep 23 2005, 05:12 PM
had developed a split on the inside wich after high revs and high heat flares open, creating a pocket in between the layers of material wich catches the fluid
Sounds like an aneurysm http://www.ae86drivingclub.com.au/forums/emoticons/biggrin.gif

It still doesn't explain how the pedal became hard as opposed to soft..... though I think I know how it would have been possible.

[ae86 slide]

well it was basicaly blocking the line, so firm pedal, anyway im stoked its fixed